数词
数词分为基数词和序数词两种。表示数目或数量多少的词叫基数词；表示数目顺序的词叫序数词。
一. 基数词
1. 基数词就注意以下几点：
（1）几十几的基数词的十位数与个位数之间要用连字符“-”连接。如：
eighty-five 85 twenty-six 26
（2）三位数的基数词须在百位和十位（若无十位则和个位）之间用and连接。如： three hundred and sixty-five 365 two hundred and six 206
（3）基数词的复数形式。当基数词hundred, thousand, million, billion等词前有具体数词或several修饰时，必须用单数。如：
several hundred year’s ago几百年前 two thousand students两千个学生
2. 基数词的特殊用法：
（1）表示“几十年代”或“几十岁”时，用逢十的基数词的复数形式。如： in the 1990’s 20世纪90年代 in o ne’s twenties在某人20多岁时
（2）用在习语中。如：
in twos and threes三三两两地
二. 序数词
序数词应注意的几点事项：
1. 多位数的基数词变成序数词时，只需将末位基数词变成序数词，前边的基数词不变。如：
forty-two 42 forty-second第42 nine-hundred 900 nine-hundredth第900
2. 当序数词用阿拉伯数字表示时，必须在数字后加上序数词的最后两个字母。如：
21st第21 32nd第32
3. 序数词前一般要用定冠词the，如果序数词前用a或an时，则表示“又一；再一”（没有具体范围的限制）。如： Though he had failed twice, he wanted to try a third time.
尽管他已失败了两次，他还想再试一次。
The little monkey had had three apples, and he wanted to eat a fourth one.
那只小猴子已经吃了3个苹果，他还想再吃一个。
三. 分数和百分数
1. 分数
（1）分数的分子用基数词，分母用序数词。如：
one fifth五分之一 one tenth十分之一
（2）当分子大于1时，分母用序数词的复数。如：
two thirds三分之二 five eighths八分之五
（3）当分子是1时，可以用one也可以用a。如：
a second = one second a third = one third
（4）当分母是2和4时，分别可以用half和quarter代替。如：
a half二分之一 three quarters四分之三
2. 百分数
百分数用percent表示。如：
forty percent百分之四十 three percent百分之三
3. 分数、百分数与主谓一致
分数、百分数的考查往往和主谓一致相联系。当分数、百分数修饰可数名词的复数时，谓语动词用复数形式；当分数、百分数修饰不可数名词时，谓语动词用单数形式。如： Eighty percent of the students in our school come from Henan.
我们学校百分之八十的学生来自河南。
Three fourths of the students in my class are interested in English.
我们班四分之三的学生对英语感兴趣。
Two thirds of the water on the earth is sea water.
地球上三分之二的水是海水。
四. 倍数的表示法
1. 表示“几倍大小（长短；数量）”，由“倍数+ the size（length, amount...）”结构组成。如：
The earth is forth-nine times the size of the moon.
2. 表示“……比……大几倍”，由“倍数+形容词（副词）比较级+ than +被比较部分”结构组成。如：
This box is three times bigger than that one.
3. 表示“……是……倍”，由“倍数+ as +形容词+ as +被比较部分”结构组成。如：
Our factory is twice as big as theirs.
数词
( ) 1. Lincoln was born on ________.
A. February 12, 1809
B. 1809, February 12
C. 1809, 12 February
D. February 1809,12 ( ) 2. A _______ boy can sing the English song very well.
A. ten-year-old
B. ten years old
C. ten-year-old
D. fifth years old
( ) 3. An hour later, _____ minister was sent to see the “magic cloth” woven by those two men. A. two B. the second C. the two D. second
( ) 4. Abraham Lincoln was _______ President of the United States.
A. 16
B. the 16
C. 16th
D. the 16th
( ) 5. Do you think there is any room for us ________ ?
A. two
B. the two
C. second
D. the second
( ) 6. --How many students are there in your class? --________.
A. Twenty nine
B. Thirty and two
C. Forty-five
D. fifties
( ) 7. Which number is wrong? _______.
A. Ninety
B. Ninteen
C. Ninth
D. Nineteenth
( ) 8. The People's Liberation Army was founded _______.
A. on August 1, 1927
B. in 1927, 1 August
C. on August 1st, 1927
D. in August 1, 1927
( ) 9. The number 4,123 is read _______.
A. four thousand one hundred and twenty-three
B. four thousand and one hundred twenty-three
C. four thousand and a hundred and twenty-three
D. four thousands a hundred and twenty-three
( ) 10. The old professor still works hard though he is _________.
A. in his sixty
B. in his sixties
C. in sixties
D. in the sixty
( ) 11. This classroom is ________ ours.
A. three times big as
B. as three times big as
C. three times as big as
D. as big three times as ( ) 12. The basketball team of our school ranks ________ in the match.
A. three
B. third
C. the three
D. the third
( ) 13. Which is the car that he drives? It's ________.
A. fifty two
B. the fifty-two cars
C. the car fifty four
D. the fifty-fourth car
( ) 14. Which of the following is wrong? ________.
A. He is a fifteen-year-old boy.
B. He is at the age of 15.
C. He is a boy of 15.
D. He is fifteen year old.
( ) 15. Our school is not very big. There are only ________ students.
A. nine hundreds of
B. nine hundred
C. nine hundreds
D. nine hundred of
( ) 16. --How many new words are there in ________ lesson?
-- There are only _________.
